Test on different exhaust !
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From: Socal - SFV
Originally Posted by SFV_S2k,Jun 30 2009, 09:16 AM
I was thinking of buying a used dyno for my own use for $60,000 and going to school for AEM. But then again my profession is in dentistry ...
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From: El Cubano que te la mete !!
Originally Posted by ChuckV,Jun 30 2009, 09:32 AM
I used a few of this "calculate ideal exhaust pipe volume" utilities, and came up with ~3" OD as being ideal for ~400hp in terms of the best combination of pulse scavenging and flow.
I kinda wonder if the mismatched TB had an effect.
Another "rule of thumb" I've always heard is that exhaust diameter should at least equal TB diameter. Strange...
I kinda wonder if the mismatched TB had an effect.
Another "rule of thumb" I've always heard is that exhaust diameter should at least equal TB diameter. Strange...
On TB ??? I don't know but another friend of mine is SC'd, has the TB matched and even has a ported head. He too gained with a smalled exhaust. He was the reason why I started to study the weirdness of smalled exhaust.
Another local friend of mine made the same hp as me back when I had the 70mm j's. He had oem headers and 63mm exhaust.
I know hellllla weird !
After going back to physics books I'm starting to develope another theory.
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From: Baraboo, WI
Originally Posted by ChuckV,Jun 28 2009, 06:32 PM
A bit premature, as I'm only THINKING about picking up another S to SC, but if I go that route, I'd most likely go with J's or T1R headers, and then the T1R 63mm cat back, or the J's 60mm unit.
This thread got me thinking, I wonder if it'd be worth talking to Hytech to have them figure out what the ideal setup would be for a supercharged F22/F20 aiming to flow enough air to make ~380-420rwhp (as this seem to be the range most SC guys shoot for).
This thread got me thinking, I wonder if it'd be worth talking to Hytech to have them figure out what the ideal setup would be for a supercharged F22/F20 aiming to flow enough air to make ~380-420rwhp (as this seem to be the range most SC guys shoot for).
If I understood him correctly he said that the exhaust has to work in conjunction with the header. (sounds logical) IE: if the header cannot flow enough to use the larger size of the exhaust the smaller exhaust will cause an increase in velocity over the larger one and thus creating what we have seen here.
?!? any thoughts? I hope that I communicated this correctly.
Brian
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From: El Cubano que te la mete !!
Originally Posted by 05S2k02Si,Jun 30 2009, 02:30 PM
I called John today and briefly explained this thread to him, as I am awaiting a header from him, and he said that it has a lot to do with the header design as well.
If I understood him correctly he said that the exhaust has to work in conjunction with the header. (sounds logical) IE: if the header cannot flow enough to use the larger size of the exhaust the smaller exhaust will cause an increase in velocity over the larger one and thus creating what we have seen here.
?!? any thoughts? I hope that I communicated this correctly.
Brian
If I understood him correctly he said that the exhaust has to work in conjunction with the header. (sounds logical) IE: if the header cannot flow enough to use the larger size of the exhaust the smaller exhaust will cause an increase in velocity over the larger one and thus creating what we have seen here.
?!? any thoughts? I hope that I communicated this correctly.
Brian
sounds 100% logical !
I just cant see why a cheap megan copy headers would work so good paired with 63 mm exhaust ?
Isn't megan 4-2-1 a copy of J's ?
I'm tempted to buy a J's and retune with 3 inch and 63mm and re-study this phenomenon !!!
Its got me thinking ...
But why would john_z car gain too? He has comptech headers 4-1 and the same thing happen???
oem>3inch megan>70mm t1r
I really hope we s2k SC guys learn more from this one !!!
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From: El Cubano que te la mete !!
Originally Posted by S2SEXY,Jun 30 2009, 07:10 PM
did you get the megan header or the knock off.the knockoff has smaller primaries if im not mistaken
I forgot ! I looked at the engraving on the exhaust roday !!!!
Ramon had the ebay one !